Formation of nanoscale wires

Abstract

Self-organized, or self-assembled, nanowires of a first composition may be used as an etching mask for fabrication of nanowires of a second composition. The method for forming such nanowires comprises: (a) providing an etchable layer of the second composition and having a buried insulating layer beneath a major surface thereof; (b) growing self-assembled nanowires on the surface of the etchable layer; and (c) etching the etchable layer anisotropically down to the insulating layer, using the self-assembled nanowires as a mask. The self-assembled nanowires may be removed or left. In either event, nanowires of the second composition are formed. The method enables the formation of one-dimensional crystalline nanowires with widths and heights at the nanometer scale, and lengths at the micrometer scale, which are aligned along certain crystallographic directions with high crystal quality. Further, the method of the present invention avoids traditional lithography methods, minimizes environmental toxic chemicals usage, simplifies the manufacturing processes, and allows the formation of high-quality one-dimensional nanowires over large areas.

Description

The present invention is related generally to electronic devices whose functional scales are measured in nanometers, and, more particularly, to forming one-dimensional epitaxial crystals with widths and heights at the nanometer scale.The synthesis of artificial low-dimensional structures to confine electrons has been a topic of scientific and technical interest for decades. Epitaxial deposition techniques have made possible the growth of two-dimensional quantum wells as thin as one atomic layer and "zero"-dimensional islands as small as a few nanometers. However, the formation of robust "one"-dimensional nanowires with a width less than 10 nm has been a major goal that has proven difficult to achieve by either epitaxial growth or lithographic processing. Various "self-assembly" techniques, in which structures form spontaneously under kinetic or thermodynamic control, have been used to grow wire-like structures directly on a semiconductor surface. Previous demonstrations include deco...

AI Technical Summary

Benefits of technology

The present invention provides a means to form essentially one-dimensional crystalline nanowires with widths and heights at the nanometer scale, and lengths at the micrometer scale, which are aligned along certain crystallographic directions with high crystal quality. Further, the present invention avoids traditional lithography methods, minimizes environmental toxic chemicals usage, simplifies the manufacturing processes, and allows the formation of high-quality one-dimensional nanowires over large areas.

Problems solved by technology

However, the formation of robust "one"-dimensional nanowires with a width less than 10 nm has been a major goal that has proven difficult to achieve by either epitaxial growth or lithographic processing.

However, they often produce wire-like structures that meander along with the steps, are terminated by single steps, have irregular shapes and sizes, and / or are not robust.

These lattice-mismatched systems will thus limit the lateral growth in all directions on the substrate surface and produce strained islands.

Such masks are ordinarily difficult to make on a nanoscale, due partly to the extremely small dimensions and due partly to the need to employ materials having differential etch rates.

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